Failing to establish a connection to server using amqp_client running on OTP26

[gmile]

Hi, all!

We're giving OTP26 a try, and it looks due to changes related to SSL defaults in OTP26, the client code is no longer able to establish a connection with the server the same way it did with OTP25.

I've posted a full repro examples on Elixirforum earlier today, but figured I'd open a discussion here too since the library we're using is essentially a wrapper around amqp_client, a source code for which is in current repo.

Note: for reference, amqp uses amqp_client to make the connection in the following places in code:

• establishing what parameters will be used to make a connection: link
• making a connection: link

In essence, I am failing to figure out correct options to pass to amqp (and subsequently to amqp_client) to bring the connection behaviour back to how it was with OTP25. Here's what I start with:

# OTP25
AMQP.Connection.open("amqp://guest:guest@amqp-issue-rabbitmq")
{:ok, %AMQP.Connection{pid: #PID<0.241.0>}}

# OTP26
AMQP.Connection.open("amqp://guest:guest@amqp-issue-rabbitmq")
# => {:error, {:auth_failure, 'Disconnected'}}

My hypothesis was that if I somehow find a way to disable SSL code path entirely, connection would work again. But I am failing miserably with a :econnrefused error:

AMQP.Connection.open("amqp://guest:guest@amqp-issue-rabbitmq", [ssl_options: :none])
# => {:error, :econnrefused}

Any suggestions for what would be the correct way to bring the connection behaviour back to how it was with OTP25?

P.S. I am happy to re-write the above example using pure amqp_client if that makes more sense to you - for now I went with what I could type faster.

[michaelklishin]

As mentioned in the Erlang compatibility doc guide, no currently released RabbitMQ version is compatible with Erlang 26.

[gmile]

@michaelklishin fair enough

Would you happen to know if there are any plans to have OTP26 support in the next minor version, for instance, in 3.12.1? Is there any on-going effort to implement OTP26 compatibility, e.g. a PR to keep track of?

[mkuratczyk]

#7845

At some point, we'll announce that 3.12.x is OTP26-compatible, but we don't know which exact version yet. The only known issues currently are dialyzer related, all tests pass on OTP26. The second problem is that we can't run the tests on Windows due to erlef/setup-beam#189.

If you can test on OTP26, that'd be useful.

Any particular reason why you are interested in OTP26?

[gmile]

@mkuratczyk thanks, appreciate the pointers 👍

Any particular reason why you are interested in OTP26?

No particular reason, no.

Some of our developers are likely to upgrade to OTP26 on their work stations soon once OTP26 becomes available in thier package managers. As an example, once this gets merged, Homebrew/homebrew-core#131104, I assume some devs in the company will receive an automatic upgrade on the next brew upgrade.

After upgrading to OTP26, devs won't be able to start the application which needs a connection to RabbitMQ server.

However, upgrading is to OTP 26 is not anything crucial for us, we can definitely pin OTP 25 everywhere and wait for support in RabbitMQ, so no pressure from us 👍

[mkuratczyk]

If they also update rabbitmq to the latest, it should work. We just don't feel comfortable saying it's supported yet, because we just recently made it pass the tests and as I mentioned, we can't even test on Windows yet. I am using OTP26 on my machine FWIW

[michaelklishin]

I use 3.12.0-rc.3 on Erlang 26 as my daily driver. 3.12.0 is just around the corner, so please give this (possibly final) RC a shot :)

[gmile]

@michaelklishin thanks, I tried but ultimately failed to use 3.12.0-rc.3 🤔

1. Added this to under the desp function in mix.exs:

   {:amqp_client,
    github: "rabbitmq/rabbitmq-server",
    tag: "v3.12.0-rc.3",
    subdir: "deps/amqp_client",
    override: true},

2. Attempted to start the app (note I am still using OTP 25, but this should be irrelevant), which failed:

   $ iex -S mix
   Erlang/OTP 25 [erts-13.2.2] [source] [64-bit] [smp:12:12] [ds:12:12:10] [async-threads:1] [jit:ns] [dtrace]
   
    GEN    clean-profile
    GEN    clean-app
    GEN    coverdata-clean
    GEN    clean-dist
    GEN    clean-ct-logs-archive
    GEN    clean-rabbitmq-deps.mk
    DEP    credentials_obfuscation ()
   Error: Unknown or invalid dependency: credentials_obfuscation.
   make: *** [erlang.mk:5105: /Users/eugene/work/contractbook/api/deps/amqp_client/deps/credentials_obfuscation] Error 78
   ** (Mix) Could not compile dependency :amqp_client, "make clean && make" command failed. Errors may have been logged above. You can recompile this dependency with "mix deps.compile amqp_client", update it with "mix deps.update amqp_client" or clean it with "mix deps.clean amqp_client"
   $
   

Any chance to have RCs of amqp_client be published on Hex to make the installation easier? Otherwise, I think I'll wait until the final release of 3.12 to try it out with OTP26.

[michaelklishin]

Previews are also published to Hex.pm. Apparently the publishing job has been failing since 3.11.14.

[gmile]

@michaelklishin I've looked briefly at the workflows in the rabbitmq/rabbitmq-server, as well at other repos - failed to see anything related to releasing of the client code. I'd be happy to see if I can do anything to fix releasing of the client code - any clues where I can find it?